Ipdecap can decapsulate traffic encapsulated within GRE, IPIP, 6in4, and ESP (IPSEC) protocols, and can also remove IEEE 802.1Q (virtual LAN) headers.
It reads packets from a pcap file, removes the encapsulation protocol, and writes them in another pcap file.

The Barefoot server is a scalable user-space port bouncer that can be used to forward, or bounce, TCP connections and UDP packets destined for an address on the host on which the Barefoot server runs to any other host or address. To these other hosts, it will appear as if the connection and packets are coming from the machine on which the Barefoot server runs, rather than from the original host. The Barefoot server has support for using proxy protocols on the outgoing side, and can relay incoming traffic out via a SOCKS server or an HTTP proxy supporting the CONNECT command. At the moment, using a proxy for outgoing traffic is only supported for the TCP protocol. The Barefoot server is targeted towards larger sites that need to bounce traffic from many simultaneous clients, while at the same time offering detailed access control, logging, and other features related to controlling the behavior of the traffic and the Barefoot server.

Netzob supports the expert in reverse engineering, evaluation, and simulation of communication protocols. Its main goals are to help security evaluators to assess the robustness of proprietary or unknown protocol implementations, simulate realistic communications to test third-party products (IDS, firewalls, etc.), and create an Open Source implementation of a proprietary or unknown protocol. Netzob provides a semi-automatic inferring process, and includes everything necessary to passively learn the vocabulary of a protocol and actively infer its grammar. The learnt protocol can afterward be simulated. Netzob handles text protocols (like HTTP and IRC), fixed field protocols (like IP and TCP), and variable field protocols (like ASN.1-based formats).

HoldingNuts is a multi-platform poker client and server. You can play the popular Texas Hold'em variant with people all over the world, meet your friends, run your own games, and even set up your own poker network.

mod_asn is an Apache module that uses BGP routing data to look up the autonomous system (AS) and the network prefix (subnet) which contains a given (client's) IP address. mod_asn is highly scalable. To do lookups in high-speed, it uses the PostgreSQL ip4r datatype, which is indexable with a Patricia Trie algorithm to store network prefixes. This is the most suitable algorithm, being able to search through around 250,000 existing prefixes quickly. mod_asn is usable as a standalone module, and the lookup result can be used by scripts or other Apache modules. For instance, a download redirector could base its decisions on the lookup result provided by mod_asn.

The goal of IP-Link is to show the relationships between different IP addresses from network traffic capture, thus quickly determining for a given address the IP address with which it communicates the most.

Netmate shows network protocols headers in 32-bit aligned fields, identical as they are represented in Requests for Comments (RFCs). It can be used to learn and teach about network protocols and to understand their functionality and collaboration.

FileZilla is a multi-platform FTP program. The suite includes an easy-to-use client, which is similar to other popular FTP programs like WS-FTP or Cute-FTP, and a Windows-only server. The client supports various flavors of FTP and SCP, including FTP over SSL/TLS (FTPS) and SSH File Transfer Protocol (SFTP). The client also features IPv6 support, support for resuming and transferring files larger than 4GB, a tabbed user interface, a powerful site manager and transfer queue, bookmarks, drag and drop support, configurable transfer speed limits, filename filters, directory comparison, a network configuration wizard, remote file editing, keep-alive, HTTP/1.1, SOCKS5, and FTP-Proxy support, logging to a file, synchronized directory browsing, and remote file search.